1. Field of the Invention
This invention generally relates to a method for producing a metal elements-resin insert, a connector block for injectors, and a method for producing the connector block for injectors, and more particularly to a metal elements-resin insert part such as an electrical wiring part for an automotive vehicle and the like and its producing method in which conductive metal elements are embedded in a resin material.
2. Description of the Prior Art
An example of a prior art method for producing a metal elements-resin insert, which is utilized in producing electrical wiring parts for an automotive vehicle, will be explained with reference to FIGS. 4A and 4B. FIG. 4A is a cross sectional view of a mold assembly for carrying out the prior art method. FIG. 4B is a cross sectional view of a produced part.
In the prior art method for producing the resin insert, when a conductive metal element 8 is embedded in a resin material 1, the metal element 8 to be inserted is pinched and held in the insert position by a pair of support pins 61 and 62 projecting into a forming cavity 50 of a mold assembly comprising a pair of upper and lower molds 31 and 32. Then, a molten resin material is poured into the forming cavity 50 and solidified therein. Produced insert 2 is taken out of the mold by disconnecting the upper mold 31 and the lower mold 32 from each other and drawing the pins 61 and 62 from the insert 2.
In the prior art method as mentioned above, since the metal element 8 is pinched by the pins 61 and 62 projecting in the upper and lower molds 31 and 32 and embedded in the resin material, drawn holes 17 caused by the support pins 61, 62 remain in the produced insert and the drawn holes 17 reach the surface of the metal element 8 (see FIG. 4B). Even if the drawn holes 17 are filled with the same resin, the surfaces of the metal element 8 have been immediately in contact with air or moisture and the filled holes are often inferior in moisture sealing capabilities. Consequently, the metal element 8 is subjected to corrosion or electrical short-circuit.